Osseoinductive magnesium-titanate implant and method of manufacturing the same

ABSTRACT

The present invention relates to a magnesium titanate oxide film implant for insertion into a living body, utilized in medical fields such as dentistry, orthopedic surgery, maxillofacial surgery and plastic surgery, and a method for preparing the same. The magnesium titanate oxide film implant in accordance with the present invention is prepared by forming a titanium oxide film (a magnesium titanate oxide film) in which magnesium is incorporated into the surface of titanium or a titanium alloy. A process for preparing a magnesium titanate oxide film implant in accordance with the present invention comprises irradiating UV light on an implant body made of titanium or a titanium alloy in distilled water for more than 2 hours; dipping the UV light-irradiated implant body in an electrolyte solution containing magnesium; and coating a magnesium titanate oxide film on the dipped implant body by anodic oxidation at a voltage of 60 to 500 V. Therefore, the present invention can provide an implant having increased bioactivity of a titanium oxide film formed by anodic oxidation, and provides an optimum magnesium titanate oxide (Ti x Mg y O z ) thickness for successful osseointegration of the magnesium titanate (Ti x ,Mg y O z ) implant.

TECHNICAL FIELD

The present invention relates to a magnesium titanate oxide film implantfor insertion into a living body, utilized in medical fields such asdentistry, orthopedic surgery, maxillofacial surgery and plasticsurgery, and a method for preparing the same.

BACKGROUND ART

Generally, titanium (or titanium alloy) implants are subjected to avariety of surface treatments to improve biocompatibility thereoffollowing lathe processing and milling. As examples of such surfacetreatment methods, mention may be made of etching in acidic/alkalinesolutions, particle blasting, plasma spray, thermal oxidation, sol-gelinduced coating using bioactive materials such as hydroxyapatite,bioglass and bioceramics, physical/chemical vapor deposition, IonImplantation or Plasma Source Ion Implantation, electrochemical anodicoxidation and applied techniques using any combination thereof.

As examples of surface treatment methods using the electrochemicalanodic oxidation among those methods, there are known a method forpreparing an oxide film using a mixed solution of sulfuric acid andhydrochloric acid, or sulfuric acid and phosphoric acid, or phosphoricacid and oxalic acid (German Patent No. 2,216,432, Japanese PatentPublication Laid-Open No. Hei 02-194,195, Swedish Patent No.1999-01973), a method for preparing an oxide film containing calcium andphosphorus (U.S. Pat. No. 5,478,237), a method involving forming ananodized film, followed by heat treatment (U.S. Pat. No. 5,354,390), amethod involving forming calcium-phosphate using anodic oxidation,followed by heat of hydration treatment so as to prepare hydroxyapatite(U.S. Pat. No. 5,354,390), a method for preparing dicalcium phosphateanhydrous (DCPA, CaHPO), tricalcium phosphate (alpha-TCP), amorphouscalcium phosphate (ACP) and dicalcium phosphate dihydrate (DCPD) (U.S.Pat. No. 5,997,62), using anodic oxidation, and a method for preparing atitanium oxide film by anodic oxidation (EP Patent Publication No. 0 676179).

However, implants in which titanium or titanium alloy was coated withthe above-mentioned calcium-phosphate or hydroxyapatite, have sufferedfrom delamination of coated materials, or biodegradation and resorptiondue to biological actions at interfaces between an implant body andcoating materials or inside coating materials, thus causing chronicinflammation of bone tissue in the vicinity of the implant, and therebyprolonged use thereof may result in continuous drop of a success rate.Further, the thicker the oxide film is, the lower the mechanicalstrength of the oxide film is, and the oxide film may be delaminatedinto bone tissue from the interface between the implant and bone tissue.

DISCLOSURE Technical Problem

Therefore, the present invention has been made in view of the aboveproblems, and it is an object of the present invention to provide amagnesium titanate oxide film implant having increased biocompatibilityand bioactivity of a titanium oxide film formed by anodic oxidation, anda process for preparing the same.

It is another object of the present invention to provide a magnesiumtitanate oxide film implant, by forming an oxide film havingosseoinductive properties and excellent mechanical strength on surfacesof titanium and titanium alloy implants, which are utilized indentistry, orthopedic surgery, otorhinolaryngology, maxillofacialsurgery and plastic surgery, so as to induce rapid and strong bonebinding, thereby leading to successful osseointegration; and a methodfor preparing the same.

Technical Solution

In accordance with an aspect of the present invention, the above andother objects can be accomplished by the provision of a magnesiumtitanate oxide film implant, comprising:

an implant body containing titanium or a titanium alloy; and

a magnesium titanate oxide film formed on the surface of the body.

In the present invention, the magnesium titanate oxide film is preparedby low voltage dielectric breakdown anodic oxidation. Preferably, themagnesium titanate oxide film contains 6 to 26% of titanium, 51 to 71%of oxygen and 1.8 to 32% of magnesium, as main ingredients; 6 to 15% ofcarbon, 0.3 to 6% of phosphorus, 0.3 to 2.1% of sodium and 1 to 2% ofnitrogen, as minor ingredients; and, sulfur, calcium and potassium in anamount of less than 1%, as additives.

In accordance with another aspect of the present invention, there isprovided a process for preparing a magnesium titanate oxide filmimplant, comprising:

irradiating UV light on an implant body made of titanium or a titaniumalloy in distilled water for more than 2 hours;

dipping the UV light-irradiated implant body in an electrolyte solutioncontaining magnesium; and

coating a magnesium titanate oxide film on the dipped implant body byanodic oxidation at a voltage of 60 to 500V.

Now, a magnesium titanate oxide film implant in accordance with thepresent invention and a process for preparing the same will be describedin detail with reference to the accompanying drawings.

The magnesium titanate oxide film implant in accordance with the presentinvention is composed of an implant body and a magnesium titanate oxidefilm formed on the surface of the implant body. The implant body used inthe present invention is made of titanium or a titanium alloy. Themagnesium titanate oxide film is formed by incorporating magnesium intothe oxide film of the implant at low voltage by dielectric breakdownanodic oxidation, and preferably, contains 1.8 to 50% of magnesium, 6 to26% of titanium and 51 to 71% of oxygen in an atomic ratio, as mainingredients, and optionally, may further contain 6 to 15% of carbon, 0.3to 6% of phosphorus, 0.3 to 2.1% of sodium, 1 to 2% of nitrogen, andtrace amounts of sulfur, calcium and potassium. Additionally, themagnesium titanate oxide film has a bilayer structure including an upperporous layer and a lower barrier oxide layer. The magnesium titanateoxide film preferably has a thickness of 300 nm to 30 μm, and morepreferably 500 nm to 10 μm.

The biochemical action mechanism of the magnesium titanate oxide filmimplant having such a constitution is as follows. The magnesium titanateoxide film implant further includes magnesium in the chemicalcomposition of a titanium oxide film, and thus, induces rapid and strongbiochemical binding between the implant and bone tissue. Mg²⁺ ionsmigrate to the outermost layer of the implant or migrate into bodilyfluids so as to cause an ion exchange reaction with Ca²⁺ ions present inthe bodily fluids, thus resulting in migration of ions. As a result, theimplant surface is electrostatically bound to bone matrix proteinshaving polyanionic properties, such as collagen type 1, thrombospondins,fibronectin, vitronectin, fibrillin, osteoadherin, osteopontin, bonesialoprotein, osteocalcin, osteonectin and BAG-75. Such electrostaticbinding between the implant and bone matrix proteins serially promotesbiomineralization around the implant. Further, the implant in accordancewith the present invention has a porous magnesium titanate surface andin turn, induces ingrowth of bone tissue into surface pores, therebyinducing a strong mechanical binding between the implant and bonetissue. That is, the porous magnesium titanate oxide film hasosseoinductive surface properties and thus the resulting synergisticeffects of biochemical and mechanical binding between the implant andbone tissue produces rapid and strong osseointegration.

Next, a process for preparing a magnesium titanate oxide film implant inaccordance with the present invention will be described.

The process for preparing a magnesium titanate oxide film implant inaccordance with the present invention comprises the steps of:irradiating UV light on an implant body in distilled water for more than2 hours; dipping the UV light-irradiated implant body in an electrolytesolution containing magnesium; and coating a magnesium titanate oxidefilm on the dipped implant body by anodic oxidation.

Specifically, details are provided on respective steps for theabove-mentioned process. The implant body is first washed and rinsedwith suitable agents such as alcohols to degrease and then UV light isirradiated on the implant body in distilled water, for more than 2hours. Irradiation of UV light on the implant body in distilled waterfor more than 2 hours is a technique affecting implantation of metalions in anodic oxidation constituting the present invention.

Then, the implant body thus irradiated is dipped in amagnesium-containing solution. The solution constituting the presentinvention is able to form a magnesium-containing titanium oxide film (amagnesium titanate oxide film, Ti_(x)Mg_(y)O_(z)) by low voltagedielectric breakdown anodic oxidation in accordance with the presentinvention, in any single or mixed solution containing magnesium, such asmagnesium acetate, magnesium phosphate, magnesium sulphate, magnesiumiodate, magnesium gluconate, magnesium nitrate, magnesium hydroxide andmagnesium chloride. In addition, the magnesium titanate oxide film inaccordance with the present invention preferably maintains magnesiumcontent in a range of 1 to 35%. For this purpose, a composition ratio ofthe above-mentioned compounds in the solution may vary. Further, inorder to adjust a pH of any single or mixed solution containingmagnesium, there may be added sulfuric acid, phosphoric acid, variousorganic acids, for example, acetic acid, oxalic acid, malic acid,succinic acid, malonic acid, and boric acid, sodium hydroxide orpotassium hydroxide as a buffering agent.

Next, using the implant as the positive electrode and platinum as thenegative electrode, a magnesium titanate oxide film is formed on thesurface of the implant by inducing microarc on the positive electrodesurface thereof at a low voltage of about 60 to 500 V. Although amechanism of forming the magnesium titanate oxide film is not fullyknown, it is believed that magnesium ions or magnesium complex ioncompounds undergo colloidal deposition by a driving force of electricfield.

The magnesium titanate oxide film in accordance with the presentinvention provides creative and exclusive chemical constitution,differing from a conventional oxide film implant. FIGS. 1 and 2 areelectron micrographs of an osseoinductive magnesium titanate oxide filmimplant after anodic oxidation in accordance with the present invention,respectively. FIG. 1 is an electron micrograph of the surface of anosseoinductive magnesium titanate oxide film, and FIG. 2 is alongitudinal cross-sectional view of the surface of the osseoinductivemagnesium titanate oxide film implant. As shown in FIG. 1, since thesurface of the magnesium titanate oxide film has a porous magnesiumtitanate surface, it may induce ingrowth of bone tissue into thosepores, thereby resulting in a strong mechanical binding between theimplant and bone tissue. As shown in FIG. 2, the osseoinductivemagnesium titanate oxide film implant in accordance with the presentinvention comprise of an implant body 1 made up of titanium or atitanium alloy and magnesium titanate oxide films 2 and 3, the magnesiumtitanate oxide film being further divided into the surface porous oxidelayer 3 and a barrier oxide layer 2 formed between the surface andimplant body.

In addition, in order to ensure prolonged and successful function of theimplant in vivo, the oxide film should have excellent mechanicalproperties (for example, compressive strength and tensile strength). Inorder to structurally reinforce mechanical properties of the titaniumoxide film containing magnesium, the present invention increases currentdensity up to 4,000 mA/cm², when performing anodic oxidation. Increasingcurrent density increases the growth rate of the barrier oxide layer onthe implant surface, and the thickness of the lower barrier oxide layer2 becomes relatively thicker, as compared to that of the surface porousoxide layer 3. As a result, the magnesium titanate oxide film inaccordance with the present invention has structural characteristicswhich are more highly resistant to external forces, as compared to theconventional oxide film implant in which the entire oxide film is filledwith pores or channels.

Further, as another method of increasing the growth rate of the titaniumoxide film containing magnesium, the temperature of the solution is keptwithin 30° C. as much as possible.

Meanwhile, the thicker the oxide film is, the lower the mechanicalstrength such as tensile strength and compressive strength of the oxidefilm is, and thus, the titanate oxide film may be delaminated into bonetissue from the interface between the implant and bone tissue. Thepresent invention provides optimized magnesium titanate oxide(Ti_(x)Mg_(y)O_(z)) thickness to effect successful osseointegration ofthe magnesium titanate oxide film implant. In order to accomplish this,at the same time, the present invention provides voltage (ranging from60 to 500 V) producing the corresponding optimized thickness formationof the oxide film.

Additionally, in order to prevent weakening of mechanical strength ofthe magnesium titanate oxide film due to chemical and structural defectsthereof resulting from capture of gas (largely, O₂, H₂), which isproduced in the course of a low voltage dielectric breakdown anodicoxidation process, on the positive electrode surface of the implant,agitation rate of a stirrer is maintained at more than 500 rpm tominimize gas adsorption on the positive electrode surface of theimplant.

Osseoinductive surface properties such as magnesium content and surfaceprocessibility, shape of the surface, and thickness of the oxide film inthe magnesium titanate oxide film may vary depending on various factorssuch as the composition ratio of the solution, applied voltage, currentdensity, solution temperature, agitation rate and pH. Except for theseproperties, the magnesium titanate oxide film in accordance with thepresent invention can be formed by using any conventional anodicoxidation methods and apparatuses.

Advantageous Effects

The present invention provides an optimum thickness of the magnesiumtitanate oxide film (Ti_(x)Mg_(y)O_(z)) to effect best successfulosseointegration of a magnesium titanate (Ti_(x)Mg_(y)O_(z)) implant.The porous magnesium titanate oxide film (Ti_(x)Mg_(y)O_(z)) inaccordance with the present invention has creative and exclusiveosseoinductive surface properties, differing from conventional oxidefilm implants. In particular, incorporation of magnesium into thechemical composition of the implant oxide film induces rapidosseointegration by biochemical binding with bone tissue (biochemicalosseointegration). Also, the porous surface structure of the oxide filminduces attachment of bone matrix proteins and ingrowth of bone tissueinto the pores, and thereby provides opportunities to reinforcemechanical osseointegration with the implant (mechanicalosseointegration). As a result, the porous magnesium titanate oxide filmimplant induces rapid and strong osseointegration due to the resultingsynergistic effects of biochemical binding and mechanical bindingbetween the implant and bone tissue, and thereby improves, on along-term basis, functionality and success rate of the titanium andtitanium alloy implants, in areas such as dentistry, orthopedic surgery,otorhinolaryngology, maxillofacial surgery and plastic surgery, so as toinduce rapid and strong bone binding, thereby leading to successfulosseointegration.

DESCRIPTION OF DRAWINGS

The above and other objects, features and other advantages of thepresent invention will be more clearly understood from the followingdetailed description taken in conjunction with the accompanyingdrawings, in which:

FIG. 1 is an electron micrograph of the surface of an osseoinductivemagnesium titanate oxide film implant in accordance with the presentinvention;

FIG. 2 is a longitudinal cross-sectional view of the surface of anosseoinductive magnesium titanate oxide film implant in accordance withthe present invention;

FIG. 3 shows results of qualitative analysis of a magnesium titanateoxide film in accordance with the present invention, by XPS analysis;

FIG. 4 shows results of qualitative analysis of Mg, among constituentsof a magnesium titanate oxide film in accordance with the presentinvention, by XPS analysis;

FIG. 5 shows results of a qualitative analysis of Ti, among constituentsof a magnesium titanate oxide film in accordance with the presentinvention, by XPS analysis;

FIG. 6 shows results of qualitative analysis of O, among constituents ofa magnesium titanate oxide film in accordance with the presentinvention, by XPS analysis;

FIGS. 7 and 8 are, respectively, electron micrographs of the surface ofa magnesium titanate oxide film in accordance with the presentinvention;

FIG. 9 is a graph showing a relationship between an increasing rate of amagnesium titanate oxide film in accordance with the present inventionand time/voltage; and

FIG. 10 is a graph showing a relationship between a thickness of amagnesium titanate oxide film in accordance with the present inventionand voltage.

BEST MODE

Now, preferred embodiments of a magnesium titanate oxide film implant inaccordance with the present invention and a process for preparing thesame will be described in detail.

Using high resolution surface analysis instruments such as X-rayPhotoelectron Spectroscopes(XPS), Auger Electron Spectroscopes (AES),Scanning Electron Microscopes (SEM), Transmission Electron Microscopes(TEM) and X-ray Diffraction (XRD), the present invention performsqualitative or quantitative characterization of osseoinductive surfaceproperties of magnesium titanate of the above-mentionedtitanium/titanium alloy implant, such as a chemical composition ofmagnesium titanate (Ti_(x)Mg_(y)O_(z)), a thickness of magnesiumtitanate, pore configurations thereof, shape and structure of surfaceand longitudinal cross-section of magnesium titanate and crystallinitythereof. Specific experimental conditions are presented in the followingExamples. These examples are provided only for illustrating the presentinvention and should not be construed as limiting the scope and sprit ofthe present invention.

Mode for Invention EXAMPLES

In accordance with Examples of the present invention, as an electrolytesolution for forming a magnesium titanate oxide film, 0.01 M to 1.0 Mmagnesium acetate, magnesium phosphate, magnesium sulphate, magnesiumiodate, magnesium gluconate, magnesium nitrate, magnesium hydroxide,magnesium chloride or ethylenediamine tetraacetic acid was used alone orin any mixed solution thereof. Further, in order to adjust pH of asingle or mixed solution to a range between 3.0 and 12.5, sulfuric acid,phosphoric acid, or various organic acids, for example, acetic acid,oxalic acid, malic acid, succinic acid, malonic acid, or boric acid wasfurther added. In addition, a buffering agent such as sodium hydroxideor potassium hydroxide was added. Where such buffering agent was added,the total concentration of the electrolyte solution increased up to 20M.

In accordance with Examples of the present invention, current density ofthe electrolyte solution containing magnesium was set to a range ofbetween 10 and 4000 mA. Additionally, in accordance with Examples of thepresent invention, voltage for performing anodic oxidation was variouslyset within a range of between DC 23 to 500 V. Further, in order toprevent chemical and/or structural weakening of mechanical strength ofthe magnesium titanate oxide film in accordance with Examples of thepresent invention, agitation rate was maintained above 500 rpm and thesolution temperature was kept below 30° C. Briefly, experimentalconditions for the above-mentioned examples are shown in Table 1 below.TABLE 1 Concentration Ingredients of of Electrolyte Current Ref.Electrolyte Solution Density Voltage No. Solution (Mol/l) (mA/cm²) (V,DC) pH 1 Magnesium 0.01-1.0 30-4000 50-500 Below acetate + 7.0 bufferingagent 2 Magnesium 0.01-1.0 30-4000 50-500 Below phosphate + 7.0buffering agent 3 Magnesium 0.01-1.0 30-4000 50-500 Below sulphate + 7.0buffering agent 4 Magnesium 0.01-1.0 120-1000  50-500 Below iodate + 7.0buffering agent 5 Magnesium 0.01-1.0 60-4000 50-500 Below gluconate +7.0 buffering agent 6 Magnesium 0.01-1.0 10-300  23-500 Below nitrate +7.0 buffering agent 7 Magnesium 0.01-1.0 30-4000 50-500 Belowhydroxide + 7.0 buffering agent 8 Magnesium 0.01-1.0 30-4000 50-500Below chloride + 7.0 buffering agent 9 Magnesium 0.01-1.0 30-2000 23-5003.5- nitrate + 12.5 acetic acid + buffering agent 10 Magnesium 0.01-1.020-4000 50-500 3.5- phosphate + 12.5 malic acid + buffering agent 11Magnesium 0.01-1.0 10-1000 50-500 3.5- acetate + oxalic 12.5 acid +buffering agent 12 Magnesium 0.01-1.0 30-4000 50-500 3.5- sulphate +12.5 ethylene- diamine tetraacetic acid + buffering agent 13 Magnesium0.01-1.0 30-4000 50-500 3.5- gluconate + 12.5 sodium hydroxide +buffering agent 14 Magnesium 0.01-1.0 30-4000 50-500 3.5- hydroxide +12.5 phosphoric acid + buffering agent 15 Magnesium 0.01-1.0 120-200050-500 3.5- iodate + acetic 12.5 acid + buffering agent 16 Magnesium0.01-1.0 50-1000 50-500 3.5- chloride + 12.5 oxalic acid + bufferingagent

Table 2 shows quantitative indication of XPS analysis on atomiccomposition of a magnesium titanate oxide film formed on the implantsurface by low voltage dielectric breakdown anodic oxidation in amagnesium-containing solution in accordance with Examples of the presentinvention. TABLE 2 Sample Sample Sample Sample Sample Sample Element 1 23 4 5 6 Ti 18.78 26.29 5.72 6.4 6.51 7.32 O 55.72 56.22 69.23 67.3556.32 50.07 Mg 1.84 2.25 13.6 15.23 25.58 32.31 C 15.24 9.57 9.44 7.027.32 6.38 P 5.86 3.1 0 1.4 0 2.4 N 1.4 2.02 0 0 0.6 1.2 S 0.3 0 0.5 0.50 0 Na 0.5 0.5 0 0 2.13 0.3 K 0 0 0 0.6 0 0 Ca 0 0 0 0 0.8 0

As can be seen from Table 2 above, magnesium titanate in accordance withthe present invention contains 6 to 26% of titanium, 51 to 71% of oxygenand 1.8 to 32% of magnesium, as main ingredients, 6 to 15% of carbon,0.3 to 6% of phosphorus, 0.3 to 2.1% of sodium and 1 to 2% of nitrogen,as minor ingredients, and sulfur, calcium and potassium in a smallamount of less than 1%.

FIGS. 3 through 6 show results of a qualitative analysis of a magnesiumtitanate oxide film in accordance with the present invention, by XPSanalysis. As can be seen from FIG. 4, magnesium shows chemical shiftingfrom 1303.96 eV up to 1302.88 eV in binding energy at Mg 1 s. This meansthat the chemical binding state of the surface of the magnesium titanateoxide film varies depending upon elemental Mg content. Such resultsindicate that values of natural numbers x, y and z in the magnesiumtitanate oxide film may vary within a constant range.

Next, varying the concentration of the electrolyte solution in themagnesium titanate oxide film imparts the following effects. Generally,in a curve showing voltage-to-time characteristics, higherconcentrations of the electrolyte solution containing magnesium drop theformation rate of the magnesium titanate oxide film, and lowersdielectric breakdown voltage. Therefore, the higher the concentration ofelectrolyte solution containing magnesium became, the higher the amountof magnesium adsorbed into the titanium oxide film became, until themagnesium content reaches 32%. FIG. 7 is an electron micrograph of asurface of a magnesium titanate oxide film in the case of a lowerconcentration of the electrolyte solution, while FIG. 8 is an electronmicrograph of a surface of a magnesium titanate oxide film in the caseof a higher concentration of the electrolyte solution. As can be seenfrom FIGS. 7 and 8, the magnesium titanate oxide film formed in thehigher concentration mixed solution has greater surface porosity, ascompared to the magnesium titanate oxide film formed in the lowerconcentration mixed solution.

In accordance with Examples of the present invention, magnesium contentin the magnesium titanate oxide film also varies depending on changes incurrent density. In general, when the current density increases up to4000 mA/cm², a formation rate of the anodized film sharply increases,and as a result, the thickness of the film also increases. Further,increased current density of up to 4000 mA/cm² contributes to anincreased pore size on the surface of the magnesium titanate oxide film,and increased surface porosity induces attachment of proteins andingrowth of bone tissue into pores, thereby reinforcing mechanicalbinding with the implant.

Next, changes in voltage at which anodic oxidation on the magnesiumtitanate oxide film occurs provides the following results. The thicknessof the magnesium titanate oxide film may increase up to several tens ofmicrometers proportional to a given voltage along with time. Forexample, in any solution given in Table 1, the thickness of the oxidefilm containing magnesium may grow up to 30 μm at a voltage of DC 500 V.Voltage for colloidal deposition of magnesium ions into the oxide filmand simultaneously, formation of pores on the surface of the magnesiumtitanate oxide film is DC 60 V. Further, since the thicker oxide filmleads to lower mechanical strength thereof (for example, tensilestrength, compressive strength), there is a great risk of delaminationof the oxide film into bone tissue from the interface between theimplant and bone tissue. Therefore, dielectric breakdown voltagenecessary for making the thickness of 300 nm to 20 μm, which is anoptimum magnesium titanate oxide film thickness for successfulosseointegration of the magnesium titanate oxide film implant, is 60 to450 V. This is a preferred voltage range by which the generated poresize and porosity of the magnesium titanate surface exertsosseoinductive properties while meeting magnesium content of more than5% in the magnesium titanate oxide film.

Although the preferred embodiments of the present invention have beendisclosed for illustrative purposes, those skilled in the art willappreciate that various modifications, additions and substitutions arepossible, without departing from the scope and spirit of the inventionas disclosed in the accompanying claims.

1. A magnesium titanate implant, comprising: an implant body containing titanium or a titanium alloy; and a magnesium titanate oxide film formed on the surface of the said implant body in a single or mixed solution containing magnesium by low voltage dielectric breakdown anodic oxidation.
 3. The magnesium titanate implant as set forth in claim 1, wherein the magnesium titanate oxide film contains 6 to 26% of titanium, 51 to 71% of oxygen and 1.8 to 32% of magnesium, as main ingredients.
 4. The magnesium titanate implant as set forth in claim 1, wherein the magnesium titanate oxide film has a bilayer structure including an upper porous layer and a lower barrier layer.
 5. The magnesium titanate implant as set forth in claim 1, wherein the magnesium titanate oxide film has a thickness of 300 nm to 30 μm.
 6. The magnesium titanate implant as set forth in claim 5, wherein the magnesium titanate oxide film has a thickness of 500 nm to 10 μm.
 7. A process for preparing a magnesium titanate oxide film implant, comprising: irradiating UV light on an implant body made of titanium or a titanium alloy in distilled water for more than 2 hours; dipping the UV light-irradiated implant body in an electrolyte solution containing magnesium; and coating a magnesium titanate oxide film on the dipped implant body by anodic oxidation at a voltage of 60 to 500V.
 8. The process as set forth in claim 7, wherein the electrolyte solution is a single or mixed solution containing magnesium.
 9. The process as set forth in claim 7 or 8, wherein the electrolyte solution has a concentration ranging from 0.1M to 1.0M.
 10. The process as set forth in claim 7 or 8, wherein the electrolyte solution has a pH of 3.0 to 12.5.
 11. The process as set forth in claim 7 or 8, wherein the current density for performing the anodic oxidation is within the range of 30 to 4000 mA/cm². 